The demolition of the Civic Arena wrapped up in March of 2012, and a broad stretch of parking spaces now occupies the space where the Igloo once stood.

Now, the gears of redevelopment could soon begin to turn for the 27-acre site in the lower Hill District, as Pittsburgh City Council is moving legislation to apply for a $20 million federal grant for the project.

On Wednesday, Council unanimously approved the legislation necessary to apply for the so-called TIGER grant, readying Hill District Councilman Daniel Lavelle's bills for final passage on Tuesday.

The funding from the Department of Transportation would be used to map out and lay down streets, sidewalks, streetlights and utility lines, said Mary Conturo, executive director of the Sports & Exhibition Authority. The city-county SEA is working closely with the project's lead developer, the Pittsburgh Penguins.

Conturo said part of the grant would be used to deal with the large amount of rainwater that flows downhill into the site from the Upper Hill District.

"We're trying to make the infrastructure as green as possible," said Conturo, noting the developers are seeking LEED certification. "We're looking to try to have the amount of stormwater that goes into the (sewer) system be less than it is right now."

That includes separating the combined Center Avenue water line into separate tubes for sewage and stormwater. Conturo said the developers also plan to use green infrastructure known as "tree reservoirs."

"The rain runoff from the streets, instead of going directly into a storm sewer, would go into a tree reservoir, which would provide water for the plantings along the roadway," Conturo said. "To the extent that there's a heavier rainfall than (the reservoirs) can handle, then there's an overflow provision that would then put it into the sewer itself."

The application for the $20 million TIGER grant is due on June 3. The process began April 29.

The redevelopment plan posited by the Penguins and the SEA includes office and retail space at the western, downtown side of the parcel, transitioning into townhouses farther up the Hill. The project is expected to cost hundreds of millions of dollars over the course of many years.